An Algorithm for Finding an Approximate Reliability Sequence for Polar Codes on the BEC

One of the most important parts of encoding and decoding in polar codes is finding the bit-channel reliability sequence, i.e., the positions of frozen bits and data bits, which has a great effect on the error correction performance. In this paper, we present an algorithm with linear complexity for determining an approximate reliability sequence in small disagreement with the true reliability sequence on the binary erasure channel (BEC).